Search Publications
Velocity profiles of [CII], [CI], CO, and [OI] and physical conditions in four star-forming regions in the Large Magellanic Cloud
Hughes, Annie; Güsten, Rolf; Okada, Yoko +4 more
Aims: The aim of our study is to investigate the physical properties of the star-forming interstellar medium (ISM) in the Large Magellanic Cloud (LMC) by separating the origin of the emission lines spatially and spectrally. The LMC provides a unique local template to bridge studies in the Galaxy and high redshift galaxies because of its low m…
Red and Reddened: Ultraviolet through Near-infrared Observations of Type Ia Supernova 2017erp
Wang, Lifan; Hsiao, E. Y.; Ruiter, Ashley J. +22 more
We present space-based ultraviolet/optical photometry and spectroscopy with the Swift Ultra-Violet/Optical Telescope and Hubble Space Telescope (HST), respectively, along with ground-based optical photometry and spectroscopy and near-infrared spectroscopy of supernova SN 2017erp. The optical light curves and spectra are consistent with a normal SN…
Kiloparsec-Scale Variations in the Star Formation Efficiency of Dense Gas: The Antennae Galaxies (NGC 4038/39)
Wilson, Christine D.; Bemis, Ashley
We study the relationship between dense gas and star formation in the Antennae galaxies by comparing Atacama large millimeter/submillimeter array (ALMA) observations of dense-gas tracers (HCN, HCO+, and HNC J = 1-0) with the total infrared luminosity (L TIR) calculated using data from the Herschel Space Observatory and the Sp…
Age gradients throughout the Galaxy with long-period variables
Evans, N. W.; Belokurov, V.; Grady, J.
We assemble the largest sample of oxygen-rich (O-rich) Miras and associated long-period variables (LPVs) to date and highlight their importance for age dating the components of the Galaxy. Using data from the Catalina Surveys and the All Sky Automated Survey for Supernovae, we extract a clean sample of ∼2200 O-rich LPVs, stretching from the Galact…
Calibrating Mg II-based Black Hole Mass Estimators with Hβ Reverberation Measurements
Park, Daeseong; Woo, Jong-Hak; Bahk, Hyeonguk
We present the new calibration of black hole mass ({M}BH}) estimators based on the Mg II λ2798 broad emission line using the Hβ reverberation-mapped (RM) sample of 31 active galactic nuclei (AGNs) that have high-quality UV spectra. The updated and enlarged sample at redshift z < 0.16 covers a large dynamic range in {M}BH} …
The geometric challenge of testing gravity with wide binaries
El-Badry, Kareem
Wide binaries provide promising laboratories for testing general relativity (GR) in the low-acceleration regime. Recent observational studies have found that the difference in the proper motions and/or radial velocities of the components of nearby wide binaries appear larger than predicted by Kepler's laws, indicating a potential breakdown of GR a…
Multiplicity of Galactic Cepheids from long-baseline interferometry. IV. New detected companions from MIRC and PIONIER observations
Kervella, P.; Anderson, R. I.; Baron, F. +10 more
Aims: We aim at detecting and characterizing the main-sequence companions of a sample of known and suspected Galactic binary Cepheids. The long-term objective is to accurately and independently measure the Cepheid masses and distances.
Methods: We used the multi-telescope interferometric combiners CHARA/MIRC and VLTI/PIONIER to detect an…
Combining multiple structural inversions to constrain the solar modelling problem
Buldgen, G.; Eggenberger, P.; Meynet, G. +12 more
Context. The Sun is the most studied of all stars, which serves as a reference for all other observed stars in the Universe. Furthermore, it also serves the role of a privileged laboratory of fundamental physics and can help us better understand processes occuring in conditions irreproducible on Earth. However, our understanding of our star is cur…
Evolution of the Stellar Mass-Metallicity Relation. II. Constraints on Galactic Outflows from the Mg Abundances of Quiescent Galaxies
Treu, Tommaso; Ellis, Richard S.; Moran, Sean M. +2 more
We present the stellar mass-[Fe/H] and mass-[Mg/H] relation of quiescent galaxies in two galaxy clusters at z ∼ 0.39 and z ∼ 0.54. We derive the age, [Fe/H], and [Mg/Fe] for each individual galaxy using a full-spectrum fitting technique. By comparing with the relations for z ∼ 0 Sloan Digital Sky Survey galaxies, we confirm our previous finding th…
Additional fluorine abundance determinations in evolved stars
de Laverny, P.; Cunha, K.; Abia, C. +2 more
We present new fluorine abundance measurements for a sample of carbon-rich asymptotic giant branch (AGB) stars and two other metal-poor evolved stars of Ba/CH types. The abundances are derived from IR, K-band, high-resolution spectra obtained using GEMINI-S/Phoenix and TNG/Giano-b. Our sample includes an extragalactic AGB carbon star belonging to …